[Morello] Capability construction and modification instructions

[Morello] Capability construction and modification instructions

SCBNDS, SCBNDSE, SCFLGS, SCOFF, SCTAG, SCVALUE.

gas/ChangeLog:

2020-10-20  Siddhesh Poyarekar  <siddesh.poyarekar@arm.com>

	* config/tc-aarch64.c (parse_operands): Add IMM6_EXT.
	* testsuite/gas/aarch64/morello_insn-c64.d: Add tests.
	* testsuite/gas/aarch64/morello_insn.d: Likewise.
	* testsuite/gas/aarch64/morello_insn.s: Likewise.

include/ChangeLog:

2020-10-20  Siddhesh Poyarekar  <siddesh.poyarekar@arm.com>

	* include/aarch64.h (aarch64_opnd): Add IMM6_EXT.

opcodes/ChangeLog:

2020-10-20  Siddhesh Poyarekar  <siddesh.poyarekar@arm.com>

	* aarch64-asm.c (aarch64_ins_aimm): Fix comment.
	* aarch64-dis.c (aarch64_ext_a64c_imm6): New function.
	* aarch64-dis.h (ext_a64c_imm6): New function.
	* aarch64-opc.c (fields): New field a64c_shift.
	(operand_general_constraint_met_p, aarch64_print_operand): Add
	IMM6_EXT.
	* aarch64-opc.h (aarch64_field_kind): Add new field.
	* aarch64-tbl.h (aarch64_opcode_table): New instructions.
	(AARCH64_OPERANDS): New operands.
	* aarch64-asm-2.c: Regenerate.
	* aarch64-dis-2.c: Regenerate.
	* aarch64-opc-2.c: Regenerate.